<?php
$src = imagecreatefromgif('kater.gif');
$color = imagecolorallocate($src, 110, 107, 242);
$color2 = imagecolorallocate($src, 92, 90, 204);
$startX = 121;
$startY = 30;
$xStep = 29;
$yStep = 20;

$dim2Mark = array(
	(int)$_GET['aa'], 
	(int)$_GET['bb'], 
	(int)$_GET['cc'], 
	(int)$_GET['ee'], 
	(int)$_GET['ff'], 
	(int)$_GET['gg'], 
	(int)$_GET['hh'], 
	(int)$_GET['ii'], 
	(int)$_GET['ll'], 
	(int)$_GET['mm'],
	(int)$_GET['nn'],
	(int)$_GET['oo'],
	(int)$_GET['q1'],
	(int)$_GET['q2'],
	(int)$_GET['q3'],
	(int)$_GET['q4']
);

$yOffset = 0;
$xOffset = 0;
foreach($dim2Mark as $k => $v) {
	$xOffset = $startX+$xStep*$v;
	$yOffset = $startY+$k*$yStep;
	if(count($dim2Mark)-1 > $k) {
		$xOffset2 = $startX + $xStep*$dim2Mark[$k+1];
		$yOffset2 = $startY+($k+1)*$yStep;
	} else {
		$xOffset2 = $xOffset;
		$yOffset2 = $yOffset;
	}
	imagelinethick($src, $xOffset, $yOffset, $xOffset2, $yOffset2, $color);
	imagerectangle($src, $xOffset, $yOffset, $xOffset+1, $yOffset+1, $color2);
}
header('Content-type:image/gif;');
imagegif($src);

function imagelinethick($image, $x1, $y1, $x2, $y2, $color, $thick = 1)
{
    /* 下面两行只在线段直角相交时好使
    imagesetthickness($image, $thick);
    return imageline($image, $x1, $y1, $x2, $y2, $color);
    */
    if ($thick == 1) {
        return imageline($image, $x1, $y1, $x2, $y2, $color);
    }
    $t = $thick / 2 - 0.5;
    if ($x1 == $x2 || $y1 == $y2) {
        return imagefilledrectangle($image, round(min($x1, $x2) - $t), round(min($y1, $y2) - $t), round(max($x1, $x2) + $t), round(max($y1, $y2) + $t), $color);
    }
    $k = ($y2 - $y1) / ($x2 - $x1); //y = kx + q
    $a = $t / sqrt(1 + pow($k, 2));
    $points = array(
        round($x1 - (1+$k)*$a), round($y1 + (1-$k)*$a),
        round($x1 - (1-$k)*$a), round($y1 - (1+$k)*$a),
        round($x2 + (1+$k)*$a), round($y2 - (1-$k)*$a),
        round($x2 + (1-$k)*$a), round($y2 + (1+$k)*$a),
    );
    imagefilledpolygon($image, $points, 4, $color);
    return imagepolygon($image, $points, 4, $color);
}